Puree of Celeriac with Pears

Place celeriac in a large saucepan. Cover with water, add 1 tablespoon lemon juice and season the water with salt. Bring to a boil. Adjust heat to maintain a gentle boil and cook, covered, for 15 minutes.

Meanwhile, peel pears and cut into 1-inch chunks. Add the pears to the pan; continue cooking until the celeriac and pears are very tender, about 10 minutes longer. Drain and puree in a food processor.

Return the puree to the pan. Stir in thyme and butter (or oil). Season with lemon juice, salt and pepper.